Large Array Defferential Scanning Calorimeter, DSC Measuring Unit

ABSTRACT

Embodiments of the present invention feature a method and apparatus for an energetics-based approach to screen and to characterize binding interactions between potential therapeutic (or diagnostic) agents and unknown target molecules. The methods and apparatus detect the occurrence of these reactions, the strength of the binding interaction and possibly the rate at which these processes take place.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit of U.S. Provisional Application No.60/930,463, filed May 16, 2007, (Attorney Docket No. 12250.0004) thecontent of which is incorporated herein by reference.

BACKGROUND

Substantial effort and funding are currently being expended in thegenomics and proteomics fields with the focus of much of this effortbeing the discovery of new therapeutic and diagnostic agents. Thesetherapeutic and diagnostic agents may work at the DNA (or RNA) level,the field of genomics, or at the protein level, the field of proteomics.In either case, the activity of a therapeutic and/or diagnostic agentresides in the ability of the drug molecule to bind tightly to aspecific target molecule and through this complex formation to alter thefunction of the target molecule.

Currently there are two prevailing approaches to evaluate howeffectively a particular drug binds with a target molecule, such as anucleic acid or protein: the structural approach and the functionalapproach. The structural approach is based on predicting the potentialof binding interactions from knowledge of the 3-D structures of theinteracting molecules. This geometric approach, which evaluates how wellthe target molecule and drug molecule might fit together, is used tominimize the number of potential drug molecules that should be studiedin detail. The functional approach is based on measurement of the changein the biological function of a nucleic acid or protein in the presenceof the therapeutic agent.

SUMMARY OF THE INVENTION

Embodiments of the present invention feature a method and apparatus foran energetics-based approach to screen and to characterize bindinginteractions between potential therapeutic (or diagnostic) agents andunknown target molecules. The methods and apparatus detect theoccurrence of these reactions, the strength of the binding interactionand possibly the rate at which these processes take place.

The methods and device utilize an array of multiple sample cells, andcorresponding sensors, thus being capable of high throughput energydetection would be desirable.

The present system also allows for the use of known robotics for thepurpose of filling the trays; moving them in and out of the system; andhaving the sensors inserted into the samples.

The present system also utilizes sensor pins. The use of a sensor pinmeans that the liquid sample around it has a shorter thermal path to thesensor—which allows for faster heat transfers to and from liquid sample.

The present system also allows for the individual cells to be adequatelysealed (e.g. so that none of the sample or solvent is evaporated orboiled out as temperatures rise). Specifically, the present system,because it utilizes the 96 well trays—which as noted above, often haveprotruding rims—is able to incorporate a sealing gasket. The sealinggasket helps maintain the integrity of the sample being tested.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic diagram of a DSC measuring unit according toone embodiment of the present invention.

FIG. 2 shows a disposable well sample plate according to one embodimentof the present invention.

FIG. 3 shows a temperature controlled block assembly (before sensorplacement) according to one embodiment of the present invention.

FIG. 4 shows a temperature controlled block assembly (after sensorplacement) according to one embodiment of the present invention.

FIG. 5 shows a sensor array and wire connections according to oneembodiment of the present invention.

FIG. 6 shows an A/D and amplifier data acquisition board according toone embodiment of the present invention.

FIG. 7 shows a sensor pin array according to one embodiment of thepresent invention.

FIG. 8 shows a cross section of the sample wells and correspondingsensor pins, according to one embodiment of the present invention.

FIG. 9 shows the lift assembly according to one embodiment of thepresent invention.

FIG. 10 shows the lower shield assembly according to one embodiment ofthe present invention.

FIG. 11 shows an internal view of the assembly block diagram accordingto one embodiment of the present invention.

FIG. 12 shows the outside of the well array according to one embodimentof the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT(S)

In FIG. 1, is shown a schematic diagram of a DCS measuring unit 100according to one embodiment of the present invention. The measuring unit100 includes a plurality of sensor pins 102. The sensor pins 102 in thisembodiment are machined out of high purity copper. They are coated witha nickel plate, and a secondary impervious gold plating on the outside.As would be appreciated, it is desirable for the sensor pins to havehigh thermal conductivity and yet be chemically inert. Accordingly, thecopper core, in this embodiment, can range from approximately 75% purein an appropriate copper alloy to 99.99% pure; the nickel plate is99.999% pure; and the gold is 99.999% pure. Nevertheless, as would beappreciated by one skilled in the art, different purity levels may, insome circumstances be adequate, and these purity levels are merely givenas examples.

It is noted that the nickel prevents gold from amalgamating with thecopper sensor pin body rendering it reactive. However, other materialsthat could serve this same function include, but are not limited tosilver and platinum. Additionally, in certain embodiments, instead ofthe core of the sensor pin 102 being copper, it could be made ofaluminum, silver, gold, platinum or any alloy or material with highthermal conductivity. Likewise, instead of utilizing gold as theoutermost surface, the sensor pins could be plated with any inertconductive metal (e.g. silver or platinum) or be constructed from inertmetals or alloys including but not limited to Hastelloy-C or tantalum.

The sensor pins 102 are designed to fit into 96 well plates commonlyused in assay techniques. The exact diameter and length of the pin 102will depend on the annulus of liquid that is desired in the well whenfilled. For example, in some analyses, a smaller liquid annulus will bedesirable, consequently, a pin 102 that is longer, or has a largerdiameter, or both would be appropriate. In some analyses a larger liquidannulus will be desirable, thus requiring a pin 102 that is shorter, hasa smaller diameter, or both. Matching the correct pin 102 size toaccount for the type of analysis being done, is a function of samplewell volume and geometry.

The sensor pins 102 are coupled to heat flow sensors 104. In thisembodiment, the heat flow sensors 104 are Peltier sensors, or Seebeckdevices. Semiconducting thermoelectric sensors (Peltier devices), aremanufactured by a number of companies, including but not limited toMelcor, Ferrotech, and Micropelt. These manufacturers produce Peltierdevices that are suitable for use as heat flow sensors in the presentinvention. However, as would be apparent to one skilled in the art,sensors could also be used. For example, other heat flow or temperaturedifference sensors that could be used in the present invention include,but are not limited to thermocouples, thermopiles, thermistors, andresistance temperature devices (RTDs).

In one embodiment, the use of thermopile sensors is contemplated.Because these types of sensors typically have lower sensitivity(Volts/Watt), modifications may also need to be made in theamplification components to account for the difference in sensitivity(as would be apparent one skilled in the art). Other types of sensorsthat could be incorporated into the present invention are RTD sensors(usually platinum or copper wound sensors) or semi-conducting thermistersensors (used in pairs). In short, any number of sensors that would beapparent to one skilled in the art could be incorporated into thepresent invention provided they are capable of measuring the temperaturedifference between sensor pin 102 and calorimeter block.

Referring again to the present embodiment containing Peltier sensors,the sensor pins 102 can be coupled to the sensors 104 in a variety ofways. For example, they can be soldered of glued to the sensors 104.

The heat flow sensors 104 in this embodiment are coupled to acalorimeter block 106. As better seen in FIGS. 3-5, in this embodiment,the calorimeter block 106 is an aluminum piece having a recess 105 intowhich the sensors 104 are placed to correspond to the sensor pins102—which in turn correspond to the wells in the 96 well plate 120.However, the calorimeter block 106 could be made from numerous otherthermally conductive materials that would be apparent to one skilled inthe art including, but not limited to, copper, gold and silver.

The calorimeter block 106 has two stages: stage I 108 and stage II 107.Between stage I and stage II is a thermal dampening material 109. Thecalorimeter block 106 is in thermal communication with a scan block 110by virtue of one or more temperature control modules 116.

Thus, in this embodiment, the temperature of stage I is activelycontrolled, and the temperature of stage II is passively controlled. Thethermal dampening materials 109 is a substance having a relatively lowthermal conductivity. For example, the dampening material 109 could be athin layer of aluminum sandwiched between thin layers of siliconerubber. The thermal gradient or temperature fluctuation dampeningmaterial could also be a single layer of low thermal conductivitymaterial (e.g. a thin sheet silicone rubber) or several thin layers ofthermally conductive material (e.g. thin sheets of aluminum) sandwichedbetween several alternating layers of insulating (or low thermalconductivity) material (e.g. thin sheets of silicone rubber). Numerousother materials for the dampening material 109 would be apparent to oneskilled in the art, provided they are capable of dampening or bufferingtemperature fluctuations or gradients in temperature by virtue of havingcomparatively lower thermal conductivity. For example, other dampeningmaterials 19 include, but are not limited to plastics, glasses,insulating foams, glass fiber or ceramic insulting materials, and layersof trapped air.

The temperature control modules 116 are the means for secondary (orfine) control of the heating rate or scanning the temperature of thecalorimeter. The temperature control modules 116 are high power semiconducting thermoelectric sensors (e.g. Peltier devices). Peltierdevices are manufactured by a number of companies, including but notlimited to Melcor, Ferrotech, and Micropelt. These manufacturers producePeltier devices that are suitable for use as temperature control modulesin the present invention. The temperature control modules 116 transfersome heat from the scan block 110 to Stage I 108 of the calorimetricblock 106. The temperature control modules 116 also provide someadditional heating power so that Stage I 108 of the calorimetric block106 and the scan block 110 are at the same temperature(ΔT=T(108)−T(106)=0). The temperature control modules 116 could bereplaced or substituted with other suitable heating devices includingbut not limited to resistive heating elements (e.g. coil or filmheaters).

The scan block 110 is the calorimeter block reference temperaturecomponent and is constructed from a significant mass of a highlythermally conductive material having a large heat capacity. In thepresent embodiment, the scan block 110 is a thick aluminum plate. Thescan block could be made from a number of other materials including butnot limited to stainless steel, copper, silver, or gold. The scan block110 is in thermal communication with one or more scan control modules114. The scan control modules 114 are the primary (or course) means forcontrolling the heating rate or scanning the temperature of thecalorimeter. The scan control modules 114 are high power semi conductingthermoelectric sensors (Peltier devices). Peltier devices aremanufactured by a number of companies, including but not limited toMelcor, Ferrotech, and Micropelt. These manufacturers produce Peltierdevices that are suitable for use as scan control modules in the presentinvention. The scan control modules 114 are able to heat the scan block110 at a regular rate (e.g. increase 1 degree per minute). The scancontrol modules 114 could be replaced with other suitable heatingdevices including but not limited to resistive heating elements (e.g.coil or film heaters).

A heat sink 112 is placed substantially over the scan control modules114 to provide a thermally stable environment in which the presentsystem 100 can operate. In the present embodiment, the heat sink 112 isa large copper block through which coolant flows during instrumentcool-down or rest cycles. The heat sink could be made from a number ofother materials having high thermal conductivity and high heat capacity,including, but not limited to stainless steel, copper, silver, or gold.The coolant connections are made through a cooper heat exchange coilrunning through the heat sink 112 and the connecting coolant lines 113.

The heat sink 112 may be kept at a constant temperature, e.g. at or nearroom temperature, or allowed to float in temperature. The large heatcapacity of the heat sink and its starting temperature as controlled bythe flowing coolant allow the heat sink to serve as a reference point incontrolling the temperature of the calorimeter and the rate at which thecalorimeter scans up in temperature. In the present embodiment, asubstantially constant temperature is maintained by a coolant line 113that runs through the heat sink 112 (also see FIG. 11). The coolant canbe water, or numerous other fluids that are capable of transferringheat, including, but not limited to other heat exchange fluids forexample antifreeze, and oil. It is also noted that the heat sink 112could be maintained at the desired temperature by other means (besides acoolant line 113), including, but not limited to a high surface area orfinned construction with fans to dissipate heat from the finned heatsink to the environment.

Over the well plate 120 is placed a well seal gasket 118. The well sealgasket 118 is a low durometer silicone sheet material. The well sealingmat or gasket could be made from a number of materials including but notlimited to viton, Teflon, neoprene or other inert non-porous soft gasketmaterials. The well seal gasket 118 includes one or more channels 126that correspond to the individual wells 128 in the 96 well plate 120.One or more protective membranes 130 are positioned over the channels126. As the individual wells 128 are raised up, the sensor pins 102puncture through the membranes 130, such that the environment in whichthe pins 102 are sensing is thermally protected to the fullest extentpossible. The membranes 130 also help prevent cross-contamination of thesamples through splashing.

The well seal gasket 118 also serves the secondary function ofcushioning the 96 well plate 120 as it is raised to insert the sensorpins 102. This cushioning helps prevent crushing of the 96 well plate120. To further cushion the 96 well plate 120, individual sensor gaskets132 could also be inserted around the sensor pins 102.

It is noted that, in the present embodiment, the 96 well plate 120 israised into communication with the sensor pins 102. However, in certainembodiments, the well plate 120 could be stationary and pins lowered.Located below the well plate 120 is an adiabatic shield 122. Theadiabatic shield provides a temperature controlled environment surroundthe sample wells. The adiabatic shield is controlled to have the sametemperature as the calorimeter blocks 106 and 108 and in the presentembodiment is constructed from a block of aluminum into which a patternof holes has been drilled to surround the sample wells of the plasticsample tray or 96 well plate 120. The adiabatic shield could be madefrom a number of other materials having high thermal conductivity andhigh heat capacity, including, but not limited to stainless steel,copper, silver, or gold. The adiabatic shield 122 is further shown inFIGS. 9 and 10. The adiabatic shield 122 includes one or more openings134 that correspond to the wells 128 of the 96 well plate 120.Specifically, as best seen in FIG. 9, the 96 well plate 120 is placedupon the adiabatic shield 122. The wells 128 insert into the openings134, and the top surface 136 (FIG. 2) of the 96 well plate 120 liessubstantially flat against the top surface 138 (FIG. 10) of theadiabatic shield 122.

The adiabatic shield 122 can be maintained at substantially the sametemperature as the scan block 110. The temperature of the adiabaticshield 122 is controlled through one or more shield control modules 124.The shield control modules 124 are high power semi conductingthermoelectric sensors (e.g. Peltier devices). Peltier devices aremanufactured by a number of companies, including but not limited toMelcor, Ferrotech, and Micropelt. These manufacturers produce Peltierdevices that are suitable for use as shield control modules in thepresent invention. The shield control modules 124 are able to heat theadiabatic shield 122 at a regular rate (e.g. increase 1 degree perminute) and keeping track with the temperature of the calorimeter blocks106 and 108. The shield control modules 124 could be replaced with othersuitable heating devices including but not limited to resistive heatingelements (e.g. coil or film heaters).

Sensor connecting wires 115 (FIG. 5) connect heat flow sensors 104 to anamplifier 117 (FIG. 6). The amplifier 117, as would be apparent to oneskilled in the art, amplifies the 96 voltage signals developed by the 96heat flow sensors 104 through wires 115. The amplified signals (fromeach of the 96 heat flow sensors) can then be collected/measured andprocessed. There are numerous off the shelf generic data acquisition(DAQ) cards and software programs available that could be applied forthese purposes. Data acquisition and control is accomplished by use of aDAQ card with the appropriate Bus Type (e.g. USB/PCI/ISA), OS support(e.g. WIN), sampling rate (>1 kS/sec), and the requisite Analog Input(multichannel, minimum resolution 16 bits), Analog output, Digital I/O,counter timer, and triggering functions. One skilled in the art ofcalorimeter design, the acquisition of low level signals, and control oftemperature using PID feedback algorithms, would be able to select asuitable off the shelf DAQ card, available from a number ofmanufacturers, including, but not limited to DataTranslation, IOTech,Microstar Laboratories, National Instruments, Sensoray, or Signatec.This processed information can then be transmitted to a personalcomputer 140 (FIG. 12), which then translates the processed signal intoreadable data. Suitable DAQ software is available from each of the DAQcard manufacturers (some are card specific). Suitable DAQ programs,include, but are not limited to DASYLab, DAPTools, DAS Wizard, andDaqViewXL. DAQ functions include all of the obvious instrument controlfunctions (e.g. timing, start, stop, seal pressure monitoring, liftactivation and positioning, gas purge, cleaning cycling, temperaturelimits, temperature equilibration, temperature control, and logging theamplified sensor voltage signals as a function of temperature).Amplified voltages are converted into apparent excess heat capacitiesfor each of the samples as a function of temperature. Data analysis interms of instrument or sample baseline signal subtraction, plotting theraw or baseline data from each of the 96 data channels, plotting ormonitoring various instrument control or check functions and fitting thedata to the appropriate thermal stability or denaturation models for thereporting of physical chemical data consistent with various models forthermal denaturation and or ligand binding by proteins and nucleic acidsis accomplished with an off the shelf software package, Cp-Calc fromCalorimetry Sciences Corporation. Another off the shelf software packagecapable of performing the DSC thermodynamic analysis is available fromOrigin (Origin 7.0). Channels 111 (FIGS. 3 and 4) can also be includedas a pathway through which the wires 115 can be thread.

Referring to FIGS. 9-11, some other features that may be included withthe present system are a lower control plate 142. The lower controlplate 142 rests underneath the shield control modules 124. In theembodiment shown in FIG. 9, the lower control plate 142 is supported ona seat lift assembly 144. The seal lift assembly 144 in FIG. 9 includesa platform 148 coupled to a pneumatic lift 150. Between the platform 148and the lower control plate 142 are one or more spacers 146. In thisembodiment, the lower control plate 142 is a thick aluminum plate, theplatform 148 is another thick aluminum plate, and the spacers 146 arealuminum rod standoffs. It is noted that other types of lifts could alsobe utilized in connection with the present system, as would be apparentto one skilled in the art. For example, the lifting could beaccomplished by a hydraulic jacking mechanism, a scissors jack, a screwjack, a chain or belt drive. As appreciated by one skilled in the art,there are numerous mechanisms that could be employed to lift theadiabatic shield 122, such that the liquid samples placed in wells 128are brought into communication with the sensor pins 102 and that thewell seal gasket 118 is compressed to complete the sealing of the samplewells. For example, in one embodiment, the spacers 146 and platform 148could be eliminated and the pneumatic lift 150 could directly raise thelower control plate 142. However, it can be advantageous to keep theadditional pieces and resultant air space simply to provide a thermallystable environment (akin to the function of the heat sink 112 discussedabove).

In some embodiments, it may even be desirable to have more than one heatsink 112—for example, a heat sink could be placed on the bottom as wellas the top of the system 100. As seen in FIS. 9 and 10, the system 100can also be encased in an enclosure 152. The enclosure 152 is made ofsheet aluminum. The enclosure could be made of from other sheet, pressedor molded materials, including, steel, stainless steel, plastic, orfiberglass. In the present embodiment the enclosure is screwed to andsupported and a chassis frame 154. As would be apparent to one skilledin the art, the frame 154 could be eliminated or made of numerousmaterials capable of providing the necessary structural supportincluding, but not limited to steel, stainless steel, or aluminum tube,angle, or flat metal stock or extrusions.

As seen in FIG. 11, the enclosure 152 can also house power supplies 156,as well as a shield 158 for electro-magnetic-field (EMF) shielding ofthe signal processing electronics (not shown). The EMF shield in thepresent embodiment is a grounded copper enclosure but could be made fromother materials including but not limited to mu metal. The shield 158helps to keep out stray interfering signals from power lines, telephonelines, radio and TV transmissions, microwave ovens, and wireless devicessuch as mobile phones, etc.

The operation of the present system, according to one embodiment, wouldbe as follows: A user would place a sample 160 in one or more wells 128of the 96 well plate 120. It is noted again that one of the advantagesof the present system is its ability to utilize the sample trays androbotics of the 96 well configuration—which are in use in other assayapplications, but heretofore unused in calorimetric science. The wellplate 120 is then placed into the corresponding openings 134 in theadiabatic shield 122. In one embodiment, the well plates 120 areintroduced through a sample tray access 162 (FIG. 12). Once the wellplate 120 is placed, the access 162 is closed, and the user raises thepneumatic lift 150, which in turn raises the platform 148, which in turnraises the adiabatic shield 122.

As the samples 160 resting in the adiabatic shield 122 rise, the sensorpins 102 press down through the membranes 130 of the well seal gasket118, and into the liquid samples contained in the sample wells 128 andcorresponding samples 160. The thermal environment surrounding thesamples 160 is then manipulated. For example, as noted above, the heatsink 112 can be maintained at a constant temperature by means of thecoolant line 113. The same temperature would be maintained by the airspace located beneath the lower control plate 142.

The scan block 110 is then heated to the desired temperature by the scancontrol modules 114. This heat is transferred, albeit imperfectly,through the temperature control modules 116 (also referred to as the ΔTcontrol modules) into the calorimeter block 106. The temperature controlmodules 116 also directly heat the calorimeter block 106. In thoseembodiments containing two stages of the calorimetric block 106—i.e.stage I 108 and stage II 107—the temperature control modules 116 are incommunication with (and consequently transfer heat to) stage I. Betweenstage I and stage II, the dampening material 109 helps to reduce thermalnoise resulting from inconsistencies in heat flow that can arise from avariety of factors. The use of the temperature control modules 116 isalso a means whereby a stable thermal environment can be created, withvery little noise that could compromise the analytical results. Thecontrol of the temperature at the sample well level and in the vicinityof the sensor pins is maintained by several levels of increasingly finercontrol employing both active and passive mechanisms. The 1^(st) levelof control is the control of the scan block 110 temperature whichresults from the application of heat (from the scan control modules 114)to achieve a controlled temperature and temperature change rate for thecalorimeter assembly. The 2^(nd) level of control is that thetemperature of stage I of the calorimeter block is maintained to be thesame temperature as the scan block by the application of small amountsof additional heat from the ΔT control modules 116. Both of these firsttwo control steps are accomplished using well known proportionalintegrated differential (PID) control strategies to achieve the desiredtemperature scan rate for the scan block and to maintain the stage Icalorimeter block temperature at the same temperature as the scan block.Both of these feedback control processes introduce signal noise as thecontrol set points are overshot in both directions. The next level ofcontrol is passive in that the stage II calorimeter block sees anaverage temperature for the stage I block. This averaging isaccomplished by the passive (and slowed down) response that results fromthe dampened coupling of the two calorimeter blocks through thedampening material 109 that separates the two calorimeter blocks 106 and108. The objective of both the active and passive control elements is toscan the temperature of the samples so that the energetics oftemperature induced chemical reactions taking place in the samples 160can be detected without interference form temperature (and heat flow)fluctuations from environmental or instrument artifact sources. Thus,the heat sensors 104 are in a substantially thermally stableenvironment. From the other end of the system 100, the adiabatic shield122 is concurrently heated to substantially the same temperature as thescan block 110. Thus, the adiabatic shield 122, the sample plate 120,the samples 160 therein, the sensor pins 102, and the heat sensors 104can all simultaneously be brought to substantially the same temperature.

Under such circumstances, a user can generate a variety of data. Forexample, the user could determine changes in the thermal stability ofdrug biotargets (e.g. receptors, proteins and nucleic acids) in thepresence or absence of potential drug compounds (or ligands) placed intothe sample wells along with the biotarget in dilute solution 128. Bysimultaneously and uniformly increasing the heat to the adiabatic shield122, as well as the calorimeter block 106, both the samples 160 and thesensors 104 are in the same thermal environment. This allows the user todetect heat capacity changes in sample solutions which are the result ofthe thermal unfolding (denaturation) of the biotarget molecules and alsothe thermal energy of the receptor/ligand interactions (drug binding orrelease). Even more useful, the present system allows this toconceivably be done on 96 samples at once.

Of course, this is just one possible application of the present system,and numerous other uses to which it may be put include, but are notlimited to, a diagnostic application in which the proteomics (or proteindistribution) in a suitable biological fluid (e.g. blood, urine,peritoneal fluid, spinal fluid, amniotic fluid, saliva) is sensed in thearray DSC by a characteristic thermal denaturation profile and withreference to an established database used to diagnose disease.

VARIATIONS OF THE PRESENT INVENTION

In certain embodiments, the scan block 110 could be in directcommunication with the control modules 116 and primary calorimeter block106. In certain embodiments the sensor array could be a monolithicdesign instead of the 96 individually place sensors 104. In certainembodiments the sensor array could have different geometry and have 384,1536, or more sensors in the obvious high throughput screeningconfigurations used in other 96 well format biotech applications. Incertain embodiments the measurement assembly could be placed in avacuum. In certain embodiments the component layout, frame, and skinassemblies could be significantly varied to achieve a more compactoverall design.

1. A calorimeter array comprising: a) one or more scan control modules;b) a scan block in thermal communication with the scan control monitors;c) one or more temperature control modules; d) a calorimetric block inthermal communication with the temperature control modules; e) one ormore heat flow sensors coupled to the calorimetric block; f) one or moresensor pins in thermal communication with the heat flow sensors. g) anadiabatic shield; h) one or more shield control modules in thermalcommunication with the adiabatic shield.
 2. The calorimeter array ofclaim 1, wherein temperature gradients in the calorimeter block areminimized using a passive low thermal conductivity dampening layer inthe construction of a two piece calorimeter block.
 3. The calorimeterarray of claim 1, wherein each of the 96 sensor signals may be used ineither a single ended or differential mode when paired with the signalfrom any other sensor in the array or an average of several otherspecifically located sensors in the array.
 4. The calorimeter array ofclaim 1, wherein the adiabatic shield is capable of receiving a 96 wellsample plate.
 5. The calorimeter array of claim 1, wherein each of the96 wells in the 96 well sample plate is sealed to a pressure adequate tocontain water at temperatures to 120° C.
 6. The calorimeter array ofclaim 1, further comprising a lift assembly capable of generating anapplied sealing force to the sealing gasket adequate to prevent loss ofwater through evaporation or boiling at temperatures to 120° C.